Question

A particle of charge `q` and mass `m` moves in a circular orbit of radius `r` with angular speed `omega`. The ratio of the magnitude of its magnetic moment to that of its angular momentum depends on
A. `q//m`
B. `2q//m`
C. `q//2m`
D. `q^2//2m`

Answer 1

Correct Answer - C
Magnetic moment is given by , `M=IA=(q)/(T) pi r^2=(2pi)/(T)(qr^2)/(2)=(omega qr^2)/(2)`
Angular momentum `=L=I omega=mr^2omega`
`therefore (M)/(L)=(omegaq r^2//2)/(mr^2omega)=(q)/(2m)`.